78 mercruiser fuel line, firing order questions

[slshoe]

First I have had top end troubles that I have another post out for, upon troubleshooting I came up with a couple questions, I replaced the plugs wires and DIST. cap. exactly the way everything was. I then looked in service manual on firing order and low and behold, it was wrong on the boat. This is how I put the wires front to back (front of motors is closest to me right?) plugs 1-4, DIST cap fires clock wise starting on the front right (while facing engine) plug which is 1, then left front 3, left back 4, right back 2. I just want to make sure I read it correct.

Second issue is when I was changing plugs I noticed a clear fuel line that goes from carb to fuel filter, the fuel filter end is not attached (I have run the boat without this attached and motor turns over fine) question is what is the purpose for this fuel line? the main fuel line is metal. When this line is attached the motor has alot harder time turning over it goes turn turn hesitate, turn turn hesitate. Then I have to try for about 15min to get boat started. without it hooked up, it starts right up. Again, Thanks in advance

Scott

 

[WillyBWright]

Re: 78 mercruiser fuel line, firing order questions

I believe that you are correct in the firing order, but it would help to know what motor.

They use a clear yellow hose to connect the vent on the fuel pump to a fitting on the carburetor so that if the fuel pump develops a gas leak, it runs into the carburetor where it burns rather than into the bilge where it could make the boat go Boom! It should have nothing to do with start-ability unless the pump has a severe leak. Needless to say, you should look into that immediately.